mori seiki nv5000 using peel mill

[Mic6]

quote:

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some ridiculous peel milling at the 43 second mark:

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You aint kiddin' That was nuts!

[Newbeeee™]

Anyone got any further info or thoughts/feedback on what is an acceptable small move etc for this toolpath?

Just wondering.

Cheers

[Matthew Hajicek - Singularity]

Gonna necro this thread 'cause this zombie just bit me.  Two dozen parts, one dozen tiny peel-milled slots per part, and my Y axis sounds like a truck horn when rapiding.  Definitely have false-brinelled flats on the balls.

[nickbe10]

I have heard of similar problems before which were traced back to insufficient motion of the tool to ensure lubrication. Can't remember what machine it was but they decided you needed at least 0.06 - 0.090 of motion to ensure proper lube. In this case there is only about 0.03. Normally this doesn't matter because usually the toolpath isn't that long so the existing lube doesn't "dry up". But over multiple 35 min peel mills you are constantly rubbing the bearing back and forth over a short distance, the lube dries up and there is insufficient motion to stimulate a fresh injection of lube and after a while you create a flat and then it is basically over......the source of this story went through 3 (yes THREE) sets of roller ways before they figured it out. Changed to a smaller endmill to give the desired motion distance and problem vanished.

Remember what the "high feed" toolpaths are for, to allow you to maintain material removal rate in less than ideal rigidity conditions.....so a 0.093 endmill might well have prevented it.

[nickbe10]

On ‎1‎/‎1‎/‎2010 at 8:35 AM, MotorCityMinion said:

Somebody step in and correct me if I'm wrong here.

You are not really wrong but this is more a heat transfer issue than anything else. The smaller the radial stepover the less time the flute is engaged in the material. Friction of the chip running up the cutting face is the source of a large proportion  of the heat generated (although kinetic impact and surface footage also play a significant part), so the "system" never generates enough heat (relatively short chip) to cause wear problems with lite radial engagements. Of course when using carbide tools you want to get the tool relatively hot compared to HSS so you increase the sfm to compensate.....a beneficial feedback loop.

[Newbeeee™]

Matt - if the axis is noisy throughout full length while rapid, could it be the thrust bearings opposed to the leadscrew?

Thrust bearings = cheap and easy change which maybe worth doing first (saturday morning job)

[mkd]

I've heard of hobby-types replacing balls rather than the whole unit. Maybe not the best idea for a commercial application.

sorry that happened. This is on a new grease lubed Haas, correct?

[Matthew Hajicek - Singularity]

On 10/21/2017 at 1:59 AM, newbeeee said:

Matt - if the axis is noisy throughout full length while rapid, could it be the thrust bearings opposed to the leadscrew?

Thrust bearings = cheap and easy change which maybe worth doing first (saturday morning job)

Could be.  I assumed it was the balls on the screw, but you never know.  I'll have to wait until the techs can look at it.